The three met in the Peach Room at Gracie Mansion at 8:30 p.m. on April 7.

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A week later, de Blasio appeared on NBC's Sunday show and said that, "like a lot of people in this country," he was waiting “to see a vision” from Clinton — a non-endorsement that some fellow Democrats criticized as an unnecessary and arrogant jab at the likely Democratic frontrunner.

Two weeks later, on April 24, he had another hour-long private meeting at Gracie Mansion, this time with Clinton’s 2016 presidential campaign advisor John Podesta, just before heading to Milwaukee on the second leg of a Midwest tour to promote his national progressive agenda.

(Later that evening, in Milwaukee, de Blasio attended a Brewers game — they played the St. Louis Cardinals — with Cardinal Timothy Dolan and Milwaukee Mayor Tom Barrett, the schedules show.)

The mayor's schedules also show a number of other private meetings de Blasio held, both at his home and at his office in City Hall.

One unusual guest he met with inside Gracie Mansion would later go on to make a significant appearance in federal prosecutors' criminal indictment of one of Albany's top legislative leaders.

On April 23, de Blasio met with Anthony Bonomo — the head of Physicians’ Reciprocal Insurers, the largest medical malpractice insurance company in the New York area and a Gov. Andrew Cuomo donor whom the governor named head of the New York Racing Association last year.

A little more than a month after he met with de Blasio, Bonomo appeared as the unnamed head of an insurance company cited in U.S. Attorney Preet Bharara's criminal complaint against Dean Skelos, then the leader of the Republican majority in the State Senate. Bharara's office said Bonomo's insurance firm had given a $100,000-a-year "no-show" job to Dean Skelos' son Adam; Bonomo has not been accused of wrongdoing.

A de Blasio spokeswoman declined to discuss the content of the meeting between de Blasio and Bonomo, saying that the office does not share details of private meetings.